Semiconductor memory devices continue to shrink in size. Semiconductor devices in general continue to shrink because device minimum feature sizes continue to shrink. Reduced feature sizes result in higher memory storage density per unit die area and reduce die cost. Memory storage density per unit die area can also be increased by increasing the efficiency with which the memory array and related circuits are organized on the die.
Outside of the memory array, decoder circuits consume the largest silicon area of repeated structures on large density die (>128 Mb). Reducing the area of the decoders will significantly increase storage density per unit die area and reduce the cost of the die.